perf(mileage): stream workbook export rows

vehicle-data-platform/apps/web/src/v2/pages/StatisticsPage.test.tsx

@@ -6,11 +6,11 @@ import StatisticsPage from './StatisticsPage';
 import { ROUTER_FUTURE } from '../routing/routerConfig';
 
 const mocks = vi.hoisted(() => ({ mileageStatistics: vi.fn(), dailyMileage: vi.fn(), vehicles: vi.fn(), vehicleCoverage: vi.fn() }));
-const exportMocks = vi.hoisted(() => ({ downloadMileageWorkbook: vi.fn() }));
+const exportMocks = vi.hoisted(() => ({ createMileageExportStream: vi.fn(), appendRows: vi.fn(), finish: vi.fn(), dispose: vi.fn() }));
 vi.mock('../../api/client', () => ({ api: mocks }));
-vi.mock('../domain/mileageExport', () => exportMocks);
+vi.mock('../domain/mileageExport', () => ({ createMileageExportStream: exportMocks.createMileageExportStream }));
 
-afterEach(() => { cleanup(); vi.restoreAllMocks(); window.localStorage.clear(); Object.values(mocks).forEach((mock) => mock.mockReset()); exportMocks.downloadMileageWorkbook.mockReset(); });
+afterEach(() => { cleanup(); vi.restoreAllMocks(); window.localStorage.clear(); Object.values(mocks).forEach((mock) => mock.mockReset()); Object.values(exportMocks).forEach((mock) => mock.mockReset()); });
 
 function renderPage(initialEntry = '/statistics') {
   const client = new QueryClient({ defaultOptions: { queries: { retry: false } } });
@@ -18,6 +18,8 @@ function renderPage(initialEntry = '/statistics') {
 }
 
 function prepareData() {
+  exportMocks.finish.mockResolvedValue(undefined);
+  exportMocks.createMileageExportStream.mockReturnValue({ appendRows: exportMocks.appendRows, finish: exportMocks.finish, dispose: exportMocks.dispose });
   mocks.mileageStatistics.mockResolvedValue({
     dateFrom: '2026-07-01', dateTo: '2026-07-14', vehicleCount: 1, recordCount: 2, sourceCount: 2,
     periodMileageKm: 193.3, fleetLatestMileageKm: 119925, averageMileagePerVin: 193.3, averageDailyMileageKm: 96.65,
@@ -188,20 +190,30 @@ test('paginates all unique vehicles when no license plate is selected', async ()
 
 test('exports the full fleet mileage with one paginated query instead of VIN batches', async () => {
   prepareData();
-  exportMocks.downloadMileageWorkbook.mockResolvedValue(undefined);
+  const exportRows = [
+    { vin: 'LTEST000000000001', plate: '粤A12345', date: '2026-07-13', startMileageKm: 119731.7, endMileageKm: 119820.4, dailyMileageKm: 88.7, source: 'GB32960' },
+    { vin: 'LTEST000000000001', plate: '粤A12345', date: '2026-07-14', startMileageKm: 119820.4, endMileageKm: 119925, dailyMileageKm: 104.6, source: 'GB32960' }
+  ];
+  mocks.dailyMileage.mockImplementation((params: URLSearchParams) => {
+    if (params.get('vehicleScope') !== 'bound') return Promise.resolve({ items: exportRows, total: 2, limit: 10000, offset: 0 });
+    const offset = Number(params.get('offset') ?? 0);
+    return Promise.resolve({ items: exportRows.slice(offset, offset + 1), total: 2, limit: 1, offset });
+  });
   renderPage('/statistics?dateFrom=2026-07-13&dateTo=2026-07-14');
   await waitFor(() => expect(screen.getByRole('button', { name: /导出 Excel/ })).toBeEnabled());
 
   fireEvent.click(screen.getByRole('button', { name: /导出 Excel/ }));
 
-  await waitFor(() => expect(exportMocks.downloadMileageWorkbook).toHaveBeenCalledTimes(1));
+  await waitFor(() => expect(exportMocks.finish).toHaveBeenCalledTimes(1));
   const exportMileageCall = mocks.dailyMileage.mock.calls[mocks.dailyMileage.mock.calls.length - 1][0] as URLSearchParams;
   expect(exportMileageCall.get('vins')).toBeNull();
   expect(exportMileageCall.get('vehicleScope')).toBe('bound');
-  expect(exportMocks.downloadMileageWorkbook.mock.calls[0][0].vehicles).toHaveLength(1);
+  expect(exportMocks.appendRows).toHaveBeenCalledTimes(2);
+  expect(exportMocks.appendRows.mock.calls.map(([rows]) => rows.map((row: { date: string }) => row.date))).toEqual([['2026-07-13'], ['2026-07-14']]);
+  expect(exportMocks.finish.mock.calls[0][0]).toHaveLength(1);
   expect(mocks.vehicleCoverage.mock.calls[mocks.vehicleCoverage.mock.calls.length - 1][1]).toBeInstanceOf(AbortSignal);
   expect(mocks.dailyMileage.mock.calls[mocks.dailyMileage.mock.calls.length - 1][1]).toBeInstanceOf(AbortSignal);
-  expect(exportMocks.downloadMileageWorkbook.mock.calls[0][1]).toBeInstanceOf(AbortSignal);
+  expect(exportMocks.createMileageExportStream.mock.calls[0][1]).toBeInstanceOf(AbortSignal);
   expect(screen.getByText(/已导出 1 辆车/)).toBeInTheDocument();
 });
 
@@ -227,7 +239,7 @@ test('shows export progress and lets the user cancel the active request', async
 
   await waitFor(() => expect(exportSignal?.aborted).toBe(true));
   expect(await screen.findByText(/已取消导出/)).toBeInTheDocument();
-  expect(exportMocks.downloadMileageWorkbook).not.toHaveBeenCalled();
+  expect(exportMocks.createMileageExportStream).not.toHaveBeenCalled();
 });
 
 test('aborts an active export when the mileage route unmounts', async () => {
@@ -248,5 +260,5 @@ test('aborts an active export when the mileage route unmounts', async () => {
   view.unmount();
 
   expect(exportSignal?.aborted).toBe(true);
-  expect(exportMocks.downloadMileageWorkbook).not.toHaveBeenCalled();
+  expect(exportMocks.createMileageExportStream).not.toHaveBeenCalled();
 });

vehicle-data-platform/apps/web/src/v2/pages/StatisticsPage.tsx

@@ -4,7 +4,7 @@ import { FormEvent, useEffect, useMemo, useRef, useState } from 'react';
 import { useSearchParams } from 'react-router-dom';
 import { api } from '../../api/client';
 import type { DailyMileageRow, MileageStatistics, Page, VehicleRow } from '../../api/types';
-import { downloadMileageWorkbook } from '../domain/mileageExport';
+import { createMileageExportStream, type MileageExportStream } from '../domain/mileageExport';
 import { formatZhNumber } from '../domain/formatters';
 import { InlineError } from '../shared/AsyncState';
 import { QUERY_MEMORY, retainPreviousPageWithinScope } from '../queryPolicy';
@@ -347,6 +347,7 @@ export default function StatisticsPage() {
     };
     setIsExporting(true);
     setExportFeedback('');
+    let exportStream: MileageExportStream | undefined;
     try {
       let vehicles: VehicleOption[] = criteria.vehicles.map((vehicle) => ({ ...vehicle }));
       if (!vehicles.length) {
@@ -362,7 +363,14 @@ export default function StatisticsPage() {
           if (offset >= result.total) break;
         }
       }
-      const mileageRows: DailyMileageRow[] = [];
+      const plateByVin = new Map(vehicles.filter((vehicle) => vehicle.plate).map((vehicle) => [vehicle.vin, vehicle.plate]));
+      exportStream = createMileageExportStream({
+        dateFrom: criteria.dateFrom,
+        dateTo: criteria.dateTo,
+        dates,
+        sources: criteria.sources.filter((source) => source.enabled),
+        exportedAt: new Date()
+      }, controller.signal);
       const vehicleBatches = criteria.vehicles.length
         ? Array.from({ length: Math.ceil(vehicles.length / EXPORT_VIN_BATCH_SIZE) }, (_, index) => vehicles.slice(index * EXPORT_VIN_BATCH_SIZE, (index + 1) * EXPORT_VIN_BATCH_SIZE))
         : [[] as VehicleOption[]];
@@ -375,24 +383,17 @@ export default function StatisticsPage() {
         while (true) {
           const params = mileageParams({ ...criteria, vehicles: vehicleBatch }, offset);
           const result = await api.dailyMileage(params, controller.signal);
-          mileageRows.push(...result.items);
+          for (const row of result.items) if (row.plate) plateByVin.set(row.vin, row.plate);
+          exportStream.appendRows(result.items);
           offset += result.items.length;
           reportProgress({ label: mileageLabel, completed: offset, total: result.total });
           if (!result.items.length || offset >= result.total) break;
         }
       }
-      const plateByVin = new Map(mileageRows.filter((row) => row.plate).map((row) => [row.vin, row.plate]));
       vehicles = vehicles.map((vehicle) => ({ ...vehicle, plate: vehicle.plate || plateByVin.get(vehicle.vin) || '' }));
       reportProgress({ label: '正在后台生成 Excel 文件' });
-      await downloadMileageWorkbook({
-        dateFrom: criteria.dateFrom,
-        dateTo: criteria.dateTo,
-        dates,
-        vehicles,
-        mileageRows,
-        sources: criteria.sources.filter((source) => source.enabled),
-        exportedAt: new Date()
-      }, controller.signal);
+      await exportStream.finish(vehicles);
+      exportStream = undefined;
       if (mountedRef.current) setExportFeedback(`已导出 ${vehicles.length} 辆车`);
     } catch (error) {
       if (mountedRef.current) {
@@ -401,6 +402,7 @@ export default function StatisticsPage() {
           : error instanceof Error ? `导出失败：${error.message}` : '导出失败，请稍后重试');
       }
     } finally {
+      exportStream?.dispose();
       if (exportControllerRef.current === controller) exportControllerRef.current = null;
       if (mountedRef.current) {
         setIsExporting(false);